lvm2: disable readline and interactive shell

lvm2: disable readline and interactive shell

remove support of interactive mode in /sbin/lvm

Benefits:
- drop dependency on readline and ncurses (-700kb if there are no other users of these libs)
- shrink the lvm binary itself (-260k)

Drawback:
- lose interactive shell:
lvm> vgchange -ay
  4 logical volume(s) in volume group "vg0" now active
lvm>

"lvm <subcommand> --params" and "<subcommand> --params" entry points are still available

Signed-off-by: Maxim Storchak <[email protected]>